Come up with a bad version of flipping a bool's value. (value = !value)

I'll start with a bad way of doing it in C# (.NET):

char[] bca = boolWert.ToString();
if (bca.Length == 4 && bca[0] == 't' && bca[1] == 'r' && bca[2] == 'u' && bca[3] == 'e')
{
boolWert = !bool.Parse($"{bca[0]}{bca[1]}{bca[2]}{bca[3]}");
}
else if (bca.Length == 5 && bca[0] == 'f' && bca[1] == 'a' && bca[2] == 'l' && bca[3] == 's' && bca[4] == 'e')
{
boolWert = !bool.Parse($"{bca[0]}{bca[1]}{bca[2]}{bca[3]}{bca[4]}");
}
else throw new Exception("y e s");